poky.conf: adjust variable whitelisting to fix sstate checksums
After some analysis of task dependencies I have adjusted the global whitelist
used to filter out variables that would otherwise cause unwanted changes in
task checksums for sstate packages.
The following changes have been made to BB_HASHBASE_WHITELIST:
* Fix typo: FILESEXTRAPATHS not FILESEXTRPATHS
* Add variables FILE_DIRNAME HOME LOGNAME SHELL TERM USER
* Remove variables DATE and TIME (these are referred to by a number of tasks
where they should affect the checksum, e.g. because they influence PV)
* Remove variable _ (not found in dependencies)
Additionally DATE and SRCDATE are excluded but only explicitly for
patch_do_patch, which uses these only to provide a warning if patches are
out of date.
Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
